U.S. patent application number 14/094878 was filed with the patent office on 2014-04-03 for cold-storage heat exchanger.
This patent application is currently assigned to DENSO CORPORATION. The applicant listed for this patent is DENSO CORPORATION. Invention is credited to Jun ABEI, Etsuo HASEGAWA, Seiji INOUE, Yoshio MIYATA, Atsushi YAMADA, Naoki YOKOYAMA.
Application Number | 20140090826 14/094878 |
Document ID | / |
Family ID | 43262906 |
Filed Date | 2014-04-03 |
United States Patent
Application |
20140090826 |
Kind Code |
A1 |
YAMADA; Atsushi ; et
al. |
April 3, 2014 |
Cold-Storage Heat Exchanger
Abstract
A cold storage heat exchanger includes multiple refrigerant
tubes having therein refrigerant passages. The refrigerant tubes
are arranged to provide a clearance therebetween. The cold storage
heat exchanger further includes a cold storage container that is
brazed with the refrigerant tube and defines a compartment
receiving a cold storage material. The cold storage container has
an open-hole portion at a brazed part with the refrigerant tube.
Accordingly, efficiency of heat exchange by the cold storage heat
exchanger can be improved.
Inventors: |
YAMADA; Atsushi; (Anjo-city,
JP) ; INOUE; Seiji; (Nukata-gun, JP) ; MIYATA;
Yoshio; (Nagoya-city, JP) ; YOKOYAMA; Naoki;
(Chiryu-city, JP) ; HASEGAWA; Etsuo; (Nagoya-city,
JP) ; ABEI; Jun; (Obu-city, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DENSO CORPORATION |
Kariya-city |
|
JP |
|
|
Assignee: |
DENSO CORPORATION
Kariya-city
JP
|
Family ID: |
43262906 |
Appl. No.: |
14/094878 |
Filed: |
December 3, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12800979 |
May 27, 2010 |
|
|
|
14094878 |
|
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Current U.S.
Class: |
165/172 |
Current CPC
Class: |
F28D 1/05391 20130101;
F28D 15/00 20130101; F25D 19/00 20130101; F28D 2020/0013 20130101;
F28F 3/025 20130101; Y02E 60/145 20130101; F28F 17/005 20130101;
F28F 3/046 20130101; F25B 39/02 20130101; F28F 1/10 20130101; F28D
1/0333 20130101; F25D 17/005 20130101; F28D 20/02 20130101; F25D
13/02 20130101; F28F 9/00 20130101; F28D 2021/0085 20130101; Y02E
60/14 20130101 |
Class at
Publication: |
165/172 |
International
Class: |
F28F 9/00 20060101
F28F009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 5, 2009 |
JP |
2009-136630 |
Apr 16, 2010 |
JP |
2010-095227 |
Claims
1. A cold storage heat exchanger comprising: a plurality of
refrigerant tubes having therein refrigerant passages, and arranged
to provide a clearance therebetween; and a cold storage container
that is brazed with the refrigerant tube and defines a compartment
receiving a cold storage material, wherein the cold storage
container has an open-hole portion at a brazed part with the
refrigerant tube.
2. The cold storage heat exchanger according to claim 1, wherein an
outer surface of the cold storage container is clad with a brazing
material containing a sacrificial protection material.
3. The cold storage heat exchanger according to claim 1, wherein an
inner surface of the cold storage container is clad with a brazing
material, and the fluidity of the brazing material on the inner
surface of the cold storage container is higher than the fluidity
of the brazing material on the outer surface of the cold storage
container.
4. The cold storage heat exchanger according to claim 1, wherein
the cold storage material directly contacts the refrigerant tube
through the open-hole portion.
5. The cold storage heat exchanger according to claim 1, wherein
the cold storage container includes a plurality of recess portions
and a plurality of protrusion portions protruding from the recess
portions, the protrusion portions of the cold storage container are
brazed with the refrigerant tubes, and the open-hole portion is
provided in each of the protrusion portions.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of U.S. application Ser.
No. 12/800,979 filed on May 27, 2010 which is based on and claims
priority to Japanese Patent Applications No. 2009-136630 filed on
Jun. 5, 2009, and No. 2010-095227 filed on Apr. 16, 2010, the
contents of which are incorporated herein by reference in its
entirety.
TECHNICAL FIELD
[0002] The present disclosure relates to a cold-storage heat
exchanger used for a refrigerant cycle device.
BACKGROUND
[0003] Conventionally, a cold-storage type cooling device for a
trucker nap, described in JP 8-175167A, is known. A container, in
which a cold-storage material is sealed, is made of a resin film,
in the cold-storage type cooling device of JP 8-175167A. A recess
portion and a protrusion portion are provided on a surface of the
container, and are configured such that an air passage for air
cooled by the cold-storage material is formed by the recess
portion.
[0004] In a cold storage time, refrigerant flows into refrigerant
tubes in which the container is inserted, so as to configure an
evaporator for a trucker nap. Thus, air passing through the air
passage is supplied to the trucker, thereby performing a cooling
operation by the evaporator.
[0005] In the above cold-storage type cooling device, an evaporator
for a vehicle interior, for cooling the trucker during a vehicle
running, is located separately from the evaporator for a trucker
nap, such that refrigerant discharged from a compressor flows into
both the evaporators in parallel.
[0006] In the above cold-storage type cooling device, a
cold-storage heat exchanger used as the evaporator for a trucker
nap only causes air to perform heat exchange with the cold-storage
material and to flow, after being cold-stored. Thus, in order to
perform the cooling of a vehicle compartment, another evaporator
used as a cooling heat exchanger is required, thereby increasing
the cost.
[0007] Furthermore, when the refrigerant tube and the cold storage
container are bonded and brazed, a clearance may be caused between
a surface of the cold storage container and a surface of the
refrigerant tube, and thereby condensed water generated on the
evaporator surface may enter into the clearance. Thus, in a case
where the refrigerant temperature is equal to or lower than
0.degree. C., the condensed water in the clearance is frozen.
[0008] When the condensed water is frozen in the clearance, the
volume of the frozen part is expanded, thereby causing a frost
break such as a break of the refrigerant tube and the cold storage
container. If a cold storage, a cooling of a compartment due to the
refrigerant tube, and a cooling of the compartment due to the cold
release of the cold storage material are performed by using a
single heat exchanger, air passes around the cold storage container
even in the cold storage time, and water in the air easily adhere
on the surface of the cold storage container. In this case, the
above problem of the frost break is remarkable.
SUMMARY
[0009] The present disclosure is made in view of the above matters,
and it is an object of the disclosure to improve a performance of a
cold storage heat exchanger as a heat exchanger.
[0010] According to an aspect of the present disclosure, a cold
storage heat exchanger includes a plurality of refrigerant tubes
having therein refrigerant passages and being arranged to provide a
clearance therebetween, and a cold storage container that is brazed
with the refrigerant tube and defines a compartment receiving a
cold storage material. The cold storage container has an open-hole
portion at a brazed part with the refrigerant tube.
[0011] Accordingly, a performance of the cold storage heat
exchanger can be improved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a schematic diagram showing a refrigerant cycle
device for a vehicle air conditioner, according to a first
embodiment of the invention;
[0013] FIG. 2 is a front view showing an evaporator according to
the first embodiment;
[0014] FIG. 3 is a side view showing the evaporator when being
viewed from the arrow III of FIG. 2;
[0015] FIG. 4 is a schematic sectional view showing a part of the
evaporator, in a section taken along the line IV-IV of FIG. 2;
[0016] FIG. 5 is a schematic sectional view showing relationships
between a refrigerant tube, a cold storage container and an
air-side fin, in a section taken along the line V-V of FIG. 3;
[0017] FIG. 6 is an inner side view of the cold storage container,
when being viewed from the arrow VI of FIG. 5;
[0018] FIG. 7 is a schematic diagram for explaining a draining
state of condensed water flowing downwardly when the evaporator of
the first embodiment is mounted in a position of a vertical
direction;
[0019] FIG. 8 is a schematic diagram for explaining a state of
discharging a treating solution in a surface processing step of the
evaporator;
[0020] FIG. 9 is an enlarged side view showing a part of a cold
storage container similar to FIG. 6, according to a second
embodiment of the invention;
[0021] FIG. 10 is a schematic sectional view showing relationships
between a refrigerant tube, a cold storage container and an
air-side fin, in a section similar to FIG. 5, according to the
second embodiment of the invention;
[0022] FIG. 11 is a characteristic diagram showing relationships
between a capacity ratio of the evaporator, and a brazing surface
ratio between the cold storage container and the refrigerant tube,
in the above first embodiment and the above second embodiment of
the invention;
[0023] FIG. 12 is a schematic diagram for explaining a flow of a
brazing material in the structure of FIG. 10;
[0024] FIG. 13 is a side view of a cold storage container having an
uneven shape of a lattice arrangement, as an example of another
embodiment of the invention;
[0025] FIG. 14 is a side view of a cold storage container having an
uneven shape of an oblique arrangement, as an example of another
embodiment of the invention;
[0026] FIG. 15 is a side view of a cold storage container having an
uneven shape of a zigzag arrangement, as an example of another
embodiment of the invention;
[0027] FIG. 16 is a side view of a cold storage container having an
uneven shape of a round lattice arrangement, as an example of
another embodiment of the invention;
[0028] FIG. 17 is a schematic sectional view showing relationships
between a refrigerant tube, a cold storage container and an
air-side fin, in a section taken along the line V-V of FIG. 3,
according to a third embodiment of the invention;
[0029] FIGS. 18A and 18B are sectional views for explaining a
performance decrease due to a bonding ratio between an inner fin
and a cold storage container of an evaporator according to the
third embodiment, in which FIG. 18A indicates a case where an outer
surface bonding ratio X is suitably small, and FIG. 18B indicates a
case where the outer surface bonding ratio X is too large;
[0030] FIGS. 19A, 19B and 19C are graphs for explaining
performances due to the bonding ratio between the inner fin and the
cold storage container of the evaporator according to the third
embodiment;
[0031] FIG. 20 is a side view showing a part of rib shape on a
surface of a cold storage container in an evaporator, according to
a fourth embodiment of the invention;
[0032] FIG. 21 is a side view showing a part of rib shape on a
surface of a cold storage container in an evaporator, according to
a fifth embodiment of the invention;
[0033] FIG. 22 is a side view showing a part of rib shape on a
surface of a cold storage container in an evaporator, according to
a sixth embodiment of the invention;
[0034] FIG. 23 is a side view showing a part of rib shape on a
surface of a cold storage container in an evaporator, according to
a seventh embodiment of the invention;
[0035] FIG. 24 is a front view showing an evaporator with a cold
storage material, formed by stacking plates, according to an eighth
embodiment of the invention;
[0036] FIG. 25 is a left side view showing the evaporator with a
cold storage material of FIG. 24;
[0037] FIGS. 26A and 26B are schematic sectional views showing in
contrast, an evaporator in which a refrigerant tube is manufactured
by a drawn-cup tube, and an evaporator in which a refrigerant tube
is manufactured by extrusion, according to the eighth embodiment of
the invention;
[0038] FIGS. 27A and 27B are schematic sectional views showing in
contrast, an evaporator in which a refrigerant tube is manufactured
by a drawn-cup tube, and an evaporator in which a refrigerant tube
is manufactured by extrusion, according to a ninth embodiment of
the invention;
[0039] FIG. 28 is a schematic sectional view showing a part of an
evaporator similar to FIG. 4, according to a tenth embodiment of
the invention;
[0040] FIG. 29 is an enlarged schematic sectional view showing a
part Z33 of FIG. 28;
[0041] FIG. 30 is an enlarged schematic sectional view showing a
part Z34 of FIG. 28;
[0042] FIG. 31 is a graph showing a variation state of an
evaporator temperature in accordance with an interruption operation
of a compressor according to a tenth embodiment of the invention;
and
[0043] FIG. 32 is a side view showing reverse V-shaped ribs formed
on a surface of a cold storage container of the evaporator of FIG.
28.
DETAILED DESCRIPTION
First Embodiment
[0044] FIG. 1 is a schematic diagram showing a refrigerant cycle
device 1 for a vehicle air conditioner, according to a first
embodiment of the invention. The refrigerant cycle device 1 for an
air conditioner includes a compressor 10, a radiator 20, a
decompression device 30 and an evaporator 40. The components of the
refrigerant cycle device 1 are connected in cycle by piping,
thereby configuring a refrigerant circuit.
[0045] The compressor 10 is driven by an internal combustion engine
(or electrical motor etc.) that is a driving source 2 for a vehicle
traveling. Thus, the compressor 10 is also stopped when the driving
source 2 stops. The compressor 10 draws refrigerant flowing out of
the evaporator 40, compresses the drawn refrigerant, and discharge
the compressed refrigerant toward the radiator 20. The radiator 20
is configured to cool high-temperature refrigerant from the
compressor 10. The radiator 20 is also called as a condenser. The
decompression device 30 decompresses the refrigerant cooled by the
radiator 20. The evaporator 40 evaporates the refrigerant
decompressed by the decompression device 30, thereby cooling air to
be blown into a vehicle compartment.
[0046] FIG. 2 is a front view showing the evaporator 40 according
to the first embodiment. FIG. 3 is a side view showing the
evaporator 40 when being viewed from the arrow III of FIG. 2. FIG.
4 is an enlarged sectional view showing a part of the evaporator
40, in a section taken along the line IV-IV of FIG. 2. FIG. 5 is a
schematic sectional view showing relationships between a
refrigerant tube, a cold storage container and an air-side fin, in
a section taken along the line V-V of FIG. 3.
[0047] In FIG. 2 and FIG. 3, the evaporator 40 includes a plurality
of branched refrigerant passage members. The refrigerant passage
members are made of metal such as aluminum. The refrigerant passage
members are formed by headers 41, 42, 43, 44 positioned by pairs,
and a plurality of refrigerant tubes 45 connected between the
headers 41, 42, 43, 44.
[0048] More specifically, as shown in FIGS. 2 and 3, a first header
41 and a second header 42 are configured as a pair of header tanks,
and are arranged in parallel to be separated by a predetermined
distance. Furthermore, a third header 43 and a fourth header 44 are
configured as a pair of header tanks, and are arranged in parallel
to be separated by a predetermined distance. The refrigerant tubes
45 are arranged at the same interval between the first header 41
and the second header 42.
[0049] The refrigerant tubes 45 corresponding to the first header
41 and the second header 42 are made to communicate with the
interiors of the first header 41 and the second header 42. Thus, a
first heat exchange portion 48 shown in FIG. 3 is formed by the
first header 41, the second header 42 and the plural refrigerant
tubes 45 arranged between the first and second headers 41 and 42.
The refrigerant tubes 45 are also arranged at the same interval
between the third header 43 and the fourth header 44.
[0050] The refrigerant tubes 45 corresponding to the third header
43 and the fourth header 44 are made to communicate with the
interiors of the third header 43 and the fourth header 44. Thus, a
second heat exchange portion 49 is formed by the third header 43,
the fourth header 44 and the plural refrigerant tubes 45 arranged
between the third and fourth headers 43 and 44.
[0051] As a result, the evaporator 40 includes the first heat
exchange portion 48 and the second heat exchange portion 49 which
are arranged at two layers. With respect to the flow direction of
air shown by arrow 400 in FIG. 3, the second heat exchange portion
49 is arranged at an upstream side, and the first heat exchange
portion 48 is arranged at a downstream side.
[0052] A joint (not shown) is provided as a refrigerant inlet at an
end portion of the first header 41 A partition plate (now shown) is
located in the first header 41 approximately at a center in a
longitudinal direction of the first header 41, to partition an
interior space of the first header 41 into a first partition area
and a second partition area. Thus, the plurality of tubes 45 is
separated into a first group and a second group based on the
partition position of the first header 41.
[0053] In the evaporator 40, refrigerant is firstly supplied to the
first partition area of the first header 41 from the refrigerant
inlet. Then, the refrigerant is distributed into the plural
refrigerant tubes 45 of the first group from the first partition
area of the first header 41. The refrigerant passing through the
plural tubes 45 of the first group flows into the second header 42,
to be joined therein.
[0054] The refrigerant flows in the second header 42, and is
distributed into the plural refrigerant tubes 45 of the second
group from the second header 42. Then, the refrigerant passing
through the plural tubes 45 of the second group flows into the
second partition area of the first header 41. Thus, in the first
heat exchange portion 48, a refrigerant path, in which refrigerant
flows in a U shape, is formed.
[0055] A joint (not shown) is provided as a refrigerant outlet at
an end portion of the third header 43. A partition plate (now
shown) is located in the third header 43 approximately at a center
in a longitudinal direction of the third header 43, to partition an
interior space of the third header 43 into a first partition area
and a second partition area.
[0056] Thus, the plurality of tubes 45 between the third header 43
and the fourth header 44 is separated into a first group and a
second group based on the partition position of the third header
43. The first partition area of the third header 43 is arranged
adjacent to the second partition area of the first header 41.
Furthermore, the first partition area of the third header 43 is
provided to communicate with the second partition area of the first
header 41.
[0057] Thus, the refrigerant flows from the second partition area
of the first header 41 to the first partition area of the third
header 43. Then, the refrigerant is distributed into the plural
refrigerant tubes 45 of the first group of the second heat exchange
portion 49 from the first partition area of the third header 43.
The refrigerant passing through the plural tubes 45 of the first
group flows into the fourth header 44, to be joined therein. The
refrigerant flows in the fourth header 44, and is distributed into
the plural refrigerant tubes 45 of the second group from the fourth
header 44, in the second heat exchange portion 49.
[0058] Then, the refrigerant passing through the plural tubes 45 of
the second group flows into the second partition area of the third
header 43. Thus, in the second heat exchange portion 49, a
refrigerant path, in which refrigerant flows in a U shape, is also
formed. The refrigerant in the second partition area of the third
header 43 flows from the refrigerant outlet toward the compressor
10.
[0059] In the evaporator 40, the plurality of tubes 45 are arranged
approximately at certain intervals, and clearances are formed
between the plural refrigerant tubes 45. A plurality air-side fins
46 and a plurality of cold-storage containers 47 are arranged in
the clearances between the plural refrigerant tubes 45, to have a
predetermined regularity. A part of the clearances between the
refrigerant tubes 45 is used as cooling air passages 460. The
remaining part in the clearances is used as receiving portions 461
in each of which the cold storage container 47 is disposed.
[0060] The receiving portions 461 are set to be in a range equal to
more than 10% and equal to or lower than 50% of the total
clearances formed between the plural refrigerant tubes 45. The cold
storage containers 47 are arranged and distributed approximately
uniformly in an entire heat exchange area of the evaporator 40. In
the example of FIG. 2, two refrigerant tubes 45 positioned at two
sides of the cold storage container 47 define the cooling air
passages 460 for exchanging heat with air on each side opposite to
the cold storage container 47.
[0061] On the other point, as shown in FIG. 4, two refrigerant
tubes 45 (45a) and 45 (45b) are arranged between the two air-side
fins 46a and 46b, and one cold storage container 47 is arranged
between the two refrigerant tubes 45 (45a) and 45 (45b).
[0062] As shown in FIGS. 4 and 5, the refrigerant tubes 45 are
multi-hole tubes each of which has a plurality of refrigerant
passages extending in a tube longitudinal direction. The
refrigerant tubes 45 (45a, 45b) are flat tubes. This multi-hole
tube can be formed by an extrusion process. A plurality of
refrigerant passages 45c shown in FIG. 4 extend in the refrigerant
tube 45 in a direction perpendicular to the paper surface of FIG.
4.
[0063] The plural refrigerant tubes 45 are arranged in plural lines
(e.g., two lines). In each arrangement line, the plural refrigerant
tubes 45 are arranged such that the side surfaces of the tubes 45
are opposite to each other. The plural refrigerant tubes 45 are
arranged to define the cooling air passages 460 for performing heat
exchange with air, and the receiving portions 461 for receiving the
cold storage containers 47, between adjacent two refrigerant tubes
45a and 45b.
[0064] In the evaporator 40, the air-side fins 46 is provided in
the cooling air passages 460 so as to increase contact areas with
air to be supplied to the vehicle compartment. In the present
embodiment, the air-side fins 46 (46a and 46b) are formed by a
plurality of corrugated fins.
[0065] The air-side fins 46 are thermally connected with the two
adjacent refrigerant tubes 45. The air-side fins 46 are bonded to
the two adjacent refrigerant tubes 45 by using a bonding material
superior in the thermal transmission. For example, a brazing
material can be used as the bonding material. The air-side fin 46
is a louver plate formed by bending a metal plate such as a thin
aluminum plate in a wave shape.
[0066] The evaporator 40 further includes the plural cold storage
containers 47. The cold storage containers 47 are made of a metal
such as aluminum, for example. The cold storage container 47 is a
cylindrical shape having concavities and convexities on its left
and right surfaces of FIG. 4.
[0067] The cold storage container 47 is closed at its longitudinal
two ends (e.g., top and bottom ends of FIGS. 2 and 5), so that a
chamber for receiving therein the cold storage material 50 is
partitioned and sealed as shown in FIG. 5. The cold storage
container 47 has main surfaces at its two side wall portions. The
two side wall portions for defining the main surfaces of the cold
storage container 47 are arranged respectively in parallel with the
refrigerant tubes 45.
[0068] The cold storage container 47 is disposed between adjacent
two refrigerant tubes 45. The cold storage container 47 is
connected thermally to the two refrigerant tubes 45 arranged
adjacently at two sides of the cold storage container 47, at
protrusion portions 47a1 of its outer shell 47a.
[0069] The cold storage container 47 is bonded to the two adjacent
refrigerant tubes 45 by using a bonding material superior in the
thermal transmission. As the bonding material, a resin material
such as a brazing material or adhesive can be used. In the first
embodiment, the cold storage container 47 is brazed to the
refrigerant tubes 45.
[0070] A brazing material is provided between the cold storage
container 47 and the refrigerant tubes 45, so as to be connected by
a larger sectional area therebetween. As the brazing material, a
brazing foil may be arranged between the cold storage container 47
and the refrigerant tube 45. In this case, the cold storage
container 47 can be bonded to the refrigerant tube 45 to have a
superior heat transmission therebetween.
[0071] The cold storage container 47 is provided with an outer
shell 47a defining an outer surface of the cold storage container
47. The outer shell 47a of the cold storage container 47 is formed
to have an uneven surface shape. In the present embodiment, by
using the uneven surface shape, the brazing performance of the cold
storage container 47 with the refrigerant tube 45 can be improved.
Because of the uneven surface shape of the outer shell 47a of the
cold storage container 47, the brazing area can be made smaller,
thereby preventing a void or a clearance from being caused.
[0072] In FIG. 5, 47a1 indicates protrusion portion (convexities),
and 47a2 indicates recess portion (concavities) of the outer shell
47a of the cold storage container 47. The protrusion portion 47a1
of the outer shell 47a of the cold storage container 47 is brazed
to the refrigerant tube 45. The brazing material contains silicon
(Si). By adjusting a silicon amount contained in the brazing
material, a degree of flux of the brazing material flowing into a
brazing portion between the cold storage container 47 and the
refrigerant tube 45 can be adjusted. The brazing material can
easily flow into the brazing portion as the amount of Si becomes
larger in the brazing material. The recess portion 47a2 of the
outer shell 47a of the cold storage container 47 defines a
cold-storage side air passage 461a.
[0073] Furthermore, the uneven shape is formed in repeat by plural
times in both of a longitudinal direction (top-bottom direction of
FIG. 5) of the cold storage container 47 and a lateral direction
(top-bottom direction of FIG. 4) of the cold storage container 47.
By the uneven surface shape of the outer shell 47a of the cold
storage container 47, draining performance of water such as
condensed water can be improved.
[0074] As shown in FIG. 5, an inner fin 47f is arranged inside of
the cold storage container 47 to be thermally and mechanically
connected to an inner wall of the cold storage container 47. The
inner fin 47f is bonded to the inner wall of the cold storage
container 47 by using a bonding material that is superior in the
heat transmission. Thus, the bonding of the inner fin 47f to the
inner wall of the cold storage container 47 can be performed by
brazing. Because the inner fin 47f is connected to the inner side
of the cold storage container 47, it can prevent a deformation of
the cold storage container 47, and pressure resistance performance
can be improved in the cold storage container 47.
[0075] As shown in FIG. 5, the inner fin 47f is formed into a wave
shape by bending a metal plate such as a thin aluminum plate.
Because the surface of the cold storage container 47 is an
uneven-shaped surface, the inner fin 47f is bonded to the recess
portion 47 of the outer shell 47a of the cold storage container 47,
that is, the inside protrusion portion protruding to the inside of
the cold storage container 47. Therefore, mechanical strength and
pressure resistance performance of the cold storage container 47
can be increased by using the inner fin 47f. Thus, the protrusion
portion 47a1 of the outer shell 47a protruding outside is not
bonded to the inner fin 47f. In FIG. 5, 460 indicates the cooling
air passage, and 461a indicates the cold-storage side air
passage.
[0076] FIG. 4 shows the inner fin 47f as a plate material when the
inner fin 47f is viewed from the top side of FIG. 5. In FIG. 5, the
inner fin 47f bent in a wave shape is schematically indicated.
Actually, a plurality of louvers are formed in the wave-shaped fin
by cutting and standing the plate material.
[0077] FIG. 6 is an inner side view of the cold storage container
47 showing an inner wall of the cold storage container 47, when
being viewed from the arrow VI of FIG. 5. The cold storage
container 47 molded by aluminum in FIG. 6 is a rectangular
container having a height dimension of about 225 mm, a width
dimension of about 50 mm, and a thickness dimension of about 5 mm,
for example. The height dimension is the dimension of the cold
storage container 47 in the top and bottom direction of FIG. 6. As
shown in FIG. 6, the plural protrusion portions 47a1 on the
container surface are formed in a zigzag arrangement. When the
plural protrusion portions 47a1 are formed in the zigzag shape on
the surface of the cold storage container 47, the container 47 can
be easily removed from a die in a press molding. Furthermore, the
lateral width dimension of the brazing portion of each protrusion
portion 47a1 is set to be equal to or lower than a width of 2-5 mm,
in order to prevent void.
[0078] Inside of the cold storage container 47 having the thickness
about 5 mm, the inner fin 47 is disposed, as shown in FIG. 5. In
FIG. 6, 47g indicates a punching-out portion configured to stop and
fix the inner fin 47. The inner fin 47f and the cold storage
material 50 are contained inside of the cold storage container 47
approximately to a height position where the punching-out portion
47g is provided. Furthermore, air is sealed in the interior of the
cold storage container 47 at an upper side of the punching-out
portion 47g. Thus, by the compression action of the air, a stress
applied to the cold storage container 47 in the expansion of the
cold storage material 50 can be reduced (refer to FIG. 5).
[0079] The operation effects of the first embodiment will be
described. In the present embodiment, the plural recess portions
47a2 and the plural protrusion portions 47a1 are provided on the
surface of the cold storage container 47. Therefore, only the outer
surfaces of the protrusion portions 47a1 are used as the contact
portion between the cold storage container 47 and the refrigerant
tube 45. Furthermore, condensed water or a treating solution used
in the evaporator surface process can be discharged easily by using
the clearance between the protrusion portions 47a1 (or/and using
the surfaces of the recess portions 47a2).
[0080] FIG. 7 is a schematic diagram for explaining a state of
condensed water flowing downwardly when the evaporator is mounted
to a vehicle air conditioner in a position of a vertical direction.
In FIG. 7, the arrows 47h1 show the streams of the condensed water
flowing in parallel from the top direction to the down direction,
on the surfaces of the recess portions 47a2 of the outer shell 47a
of the cold storage container 47, between the protrusion portions
47a1 arranged in a zigzag shape.
[0081] Because of the protrusion portions 47a1, it can prevent a
flat contact in a wide area, thereby preventing a void generation
in the brazing portion after the brazing. Therefore, the brazing
performance between the cold storage container 47 and the
refrigerant tube 45 can be improved.
[0082] In the present embodiment, the plural recess portions 47a2
and the plural protrusion portions 47a1 are provided on the surface
of the cold storage container 47. Therefore, only the inside
protrusions of the recess portions 47a2 can be made to contact the
inner fin 47f of the cold storage container 47.
[0083] As a result, an inner path 50a can be secured between the
inner fin 47f and the cold storage container 47. Thus, in a sealing
step for sealing the cold storage material 50, a time for sealing
the cold storage material 50 can be effectively shortened.
[0084] FIG. 8 is a schematic diagram for explaining a state of
removing a treating solution in a surface processing step of the
evaporator. After the dipping of the cold storage container 47 is
performed in a treating solution, air is blown by a blower to the
cold storage container 47. In FIG. 8, the arrows 47h2 show the
streams of the treating solution flowing on the surfaces of the
recess portions 47a2 of the cold storage container 47 between the
protrusion portions 47a1 arranged in a zigzag shape. Furthermore,
471 and 472 indicate the direction of air blown by the blower in
the surface processing step.
[0085] Because the uneven shape of the cold-storage container 47 is
repeated in the longitudinal direction and the lateral direction of
the cold storage container 47, the draining performance can be
secured regardless of the mounting angle of the evaporator. In
particular, it is preferable to provide thin and long oval
protrusion portions 47a1 along the longitudinal direction of the
cold storage container 47, as shown in FIG. 7. In this case, the
draining performance of the condensed water, press-molding
performance of the cold storage container 47, and sealing
performance of the cold storage material 50 can be more
improved.
Second Embodiment
[0086] Next, a second embodiment of the invention will be
described. FIG. 9 is a side view showing a cold storage container
47 according to the second embodiment, corresponding to that of
FIG. 6. In the present embodiment and the following embodiments, a
part that corresponds to a matter described in the above first
embodiment may be assigned with the same reference numeral, and the
explanation for the part may be omitted. Only different structures
and features different from the above-described first embodiment
will be mainly described in the present embodiment and the
following embodiments.
[0087] As shown in FIG. 9, in the second embodiment, the cold
storage container 47 is provided with plural protrusion portions
47a1 each having an open-hole shape at its center portion (i.e.,
protrusion tip surface). As shown in FIG. 10, via open-hole
portions 47a3 opened at the protrusion portions 47a1, the cold
storage material 50 in the cold storage container 47 can directly
contact the surface of the refrigerant tube 45.
[0088] Further, it is preferable to set the brazing width of the
protrusion portion 47a1 in the left-right direction of FIG. 9 to be
in a range of 2 mm to 5 mm.
[0089] FIG. 10 is an enlarged sectional view showing relationships
between the refrigerant tube 45, the cold storage container 47 and
the air-side fin 46, similarly to FIG. 5. The cold storage material
50, sealed in the cold storage container 47 together with the inner
fin 47f, exposes from the inside of the cold storage container 47
into the open-hole portions 47a3, thereby directly contacting the
surface of the refrigerant tube 45. In FIG. 10, 460 indicates the
cooling air passage, and 461a indicates the cold-storage side air
passage.
[0090] After the protrusion portions 47a1 of the cold storage
container 47 are brazed to the refrigerant tube 45, the cold
storage material 50 is sealed in the cold storage container 47 by
the surface of the refrigerant tube 45. Thus, it can prevent the
cold storage material 50 from leaking from the open-hole portions
47a3 of the cold storage container 47.
[0091] A contact area is set at 100% as a reference, if all the
outer surface of a cold storage container 47 without an uneven
shape (i.e., without the recess portions 47a2 and the protrusion
portions 47a1) or without the open-hole portion 47a3 is used as the
contact surface contacting the surface of the refrigerant tube 45.
In this case, when the uneven shapes or/and the hole-open portions
47a3 are provided in the outer surface of the cold storage
container 47 so that the contact area of the cold storage container
47 partially contacting the refrigerant tube 45 becomes equal to or
larger than 10% (more preferably, equal to or larger than 20%) as
in the first and second embodiments, the heat exchanging capacity
can be sufficiently obtained in the evaporator for an air
conditioner, as described later. Here, the contact area corresponds
to a brazing area.
[0092] FIG. 11 is a characteristic diagram showing relationships
between a capacity ratio of the evaporator, and a brazing surface
ratio between the cold storage container 47 and the refrigerant
tube 45. In FIG. 11, the capacity ratio of the evaporator is set at
100%, when the brazing area ratio is set at 100% in a case where
all the outer surface of the cold storage container 47 without an
uneven shape or without the open-hole portion 47a3 is used as the
contact surface contacting the surface of the refrigerant tube 45.
As shown in FIG. 11, even when the cold storage container 47 is
provided with the uneven shape or the open-hole portions at the
protrusion portions 47a1, when the ratio of the brazing area
partially contacting the refrigerant tube 45 is set equal to or
larger than 10%, the capacity ratio of the evaporator can be
maintained equal to or larger than 90%.
[0093] In a case where the open-hole portions 47a3 are provided, it
is preferable to use a brazing material formed on the inner surface
of the cold storage container 47 to be different from a brazing
material formed on the outer surface of the cold storage container
47, as the brazing materials used at the brazing portion between
the cold storage container 47 and the refrigerant tube 45. The
fluidity of the brazing material becomes larger, as an amount of
silicon Si contained in the brazing material becomes larger.
[0094] FIG. 12 is a schematic diagram for explaining a flow of a
brazing material in the structure of FIG. 10. In FIG. 12, arrow
471N indicates a flow of an inner-surface brazing material formed
on an inner surface of the cold storage container 47, and arrow
47OUT indicates a flow of an outer-surface brazing material formed
on an outer surface of the cold storage container 47.
[0095] The fluidity of the brazing material becomes larger, as an
amount of silicon Si contained in the brazing material becomes
larger. When the fluidity of the inner-surface brazing material of
the cold storage container 47 is made higher than the fluidity of
the outer-surface brazing material of the cold storage container
47, the brazing of the cold storage container 47 to the refrigerant
tube 45 can be preferably performed. The reason will be explained
below.
[0096] The outer-surface brazing material of the cold storage
container 47 includes a sacrificial anticorrosion material. By
limiting the fluidity of the outer-surface brazing material flowing
into between the cold storage container 47 and the refrigerant tube
45, the brazing at a necessary portion due to the outer-surface
brazing material can be secured, and it is preferable to improve
the anticorrosion performance of the brazing portion between the
cold storage container 47 and the refrigerant tube 45. Thus, in the
present embodiment, the silicon Si amount is made larger in the
inner-surface brazing material of the cold storage container 47
than that in the outer-surface brazing material of the cold storage
container 47, thereby increasing the fluidity of the inner-surface
brazing material shown by the arrow 471N in FIG. 12.
[0097] In the present embodiment, because the brazing of the
brazing portion between the cold storage container 47 and the
refrigerant tube 45 is performed by using both the flow of the
inner-surface brazing material flowing from the inner surface of
the cold storage container 47 and the flow of the outer-surface
brazing material flowing from the outer surface of the cold storage
container 47, the bonding performance of the cold storage container
47 to the refrigerant tube 45 can be effectively obtained and
maintained.
(Modification of the Above-Described First and Second
Embodiments)
[0098] The invention is not limited to the above-described
embodiments, but the following changes and modifications will
become apparent to those skilled in the art. For example, in the
above-described first embodiment, the zigzag uneven shape is formed
on the surface of the cold storage container 47. However, as shown
in FIG. 13, a grill-arrangement oval-uneven shape may be formed on
the surface of the cold storage container 47. Moreover, an uneven
shape of the cold storage container 47 may be an oval-shaped
slanting arrangement shown in FIG. 14, may be a round zigzag
arrangement shown in FIG. 15, or may be a round grill arrangement
shown in FIG. 16.
Third Embodiment
[0099] FIG. 17 is an enlarged sectional view showing relationships
between a refrigerant tube, a cold storage container and an
air-side fin, according to a third embodiment, in a section taken
along the line V-V of FIG. 3 similarly to FIG. 5. In the third
embodiment, a bonding ratio of the outer surface of the cold
storage container 47 or a bonding ratio of the inner surface of the
cold storage container 47 is set in a predetermined range.
[0100] In FIG. 17, 460 indicates a cooling air passage, and 461a
indicates a cold-storage side air passage. In a case where the
surface of the cold storage container 47 is configured to have ribs
of an uneven shape, when an area ratio of the outer surface of the
cold storage container 47 defining the protrusion portions 47a1 is
set at X %, and when an area ratio of the inner surface of the cold
storage container 47 defining the recess portion 47a2 is set at Y
%, X+Y=100%. Here, the outer surface of the cold storage container
47 defining the protrusion portion 47a1 is the portion of the
virtual lines indicated by the chain lines in FIG. 17. In contrast,
the inner surface of the cold storage container 47 defining the
recess portion 47a2 is the portion of the cold storage container 47
contacting the inner fin 47f.
[0101] As shown in FIG. 17, the inner fin 47f having a uniform
width is provided in the cold storage container 47. By forming the
uneven shape of the surface of the cold storage container 47, the
inner fin 47f is made to partially contact the inner surface of the
cold storage container 47 and to partially not contact the inner
surface of the cold storage container 47. When the area ratio X of
the virtual line portion of the cold storage container 47 is large,
that is, when the area ratio Y of the recess portion 47a2 is small,
a ratio of the non-contact area between the cold storage container
47 and the inner fin 47f becomes large, thereby reducing the
performance of the heat exchanger (e.g., evaporator).
[0102] On the other hand, when the area ratio X of the virtual line
portion is small, that is, when the area ratio Y is large, it is
difficult to have a sufficient contact area between the cold
storage container 47 and the refrigerant tubes 45 (45a, 45b). In
this case, the amount of the cold storage material and the amount
of the brazing material can be made small, but heat exchanging
performance of a cold storage heat exchanger (e.g., evaporator) is
reduced.
[0103] The inner fin 47f is bent in a wave shape to have ending
portions, so that the tip portions of the bending portions
partially contact the inner surface of the cold storage container
47. The wave height of the bending portions (i.e., the width of the
inner fin 17 in the left-right direction of FIG. 17) is made
uniform. When the wave height of the bending portions of the inner
fin 47f is made uniform, the inner fin 47f can be easily
manufactured and assembled.
[0104] FIGS. 18A and 18B are schematic diagrams for explaining a
decrease in heat exchange performances due to the bonding ratio
between the inner fin 47f and the cold storage container 47. FIG.
18A shows a case where the area ratio (bonding ratio) X of the
outer surface of the cold storage container 47 is in a suitable
range, and FIG. 18B shows a case where the bonding ratio X of the
outer surface of the cold storage container 47 is too large.
[0105] In the case of FIG. 18A, the heat transmission distance from
the refrigerant tubes 45a, 45b to the inner fin 47f and to the cold
storage material 50 is made shorter, thereby increasing heat
transmission amount. In contrast, in the case of FIG. 18B, the heat
transmission distance from the refrigerant tubes 45a, 45b to the
inner fin 47f and to the cold storage material 50 is made longer,
thereby decreasing heat transmission amount.
[0106] Because of the uneven portion is provided in the cold
storage container 47, a part of the inner fin 47f does not contact
the cold storage container 47, and is not brazed to the inner wall
of the cold storage container 47. Thus, the performance of the cold
storage heat exchanger is changed by the uneven shape and
dimension.
[0107] FIGS. 19A, 19B and 19C are graphs for explaining the heat
exchange performances due to the bonding ratio between the inner
fin 47f and the cold storage container 47. FIG. 19A is a graph
showing the relationship between a bonding ratio X and a cold
release time after the cold storage material 50 is sufficiently
cold-stored. FIG. 19B is a graph showing the relationship between
the bonding ratio X and a cold storage time (Seconds). FIG. 19C is
a graph showing the relationship between a bonding ratio X and a
cold release time (Seconds) when the cold storage is performed for
a limited time and is not completely finished.
[0108] In FIGS. 18A-18B and FIGS. 19A-19C, when the bonding ratio X
becomes larger, the volume of the cold storage material 50 at a
portion adjacent to the bonding portion is increased. Therefore, in
a case where cold storage is sufficiently performed for the cold
storage material 50, the cold release time becomes larger as the
bonding ratio X increases, as in the graph of FIG. 19A.
[0109] Here, the time for solidifying all the cold storage material
50 is defined as the cold storage time. In this case, when the
bonding ratio X becomes larger as in FIG. 18B, the heat
transmission path for transmitting heat to the inside of the cold
storage material 50 becomes longer as in FIG. 18B, and thereby the
heat exchange efficiency of the air-side fins 46 (46a, 46b) is
decreased.
[0110] Therefore, as in the graph of FIG. 19B, when the bonding
ratio X is large, the cold storage time becomes pretty large.
Furthermore, the time, for which the cold storage can be performed,
is a limited time having a relation with the driving time of a
vehicle. Therefore, it is necessary to effectively use the cold
storage material 50 mounted in the vehicle, and to completely
perform the cold storage of the cold storage material 50. In the
graph of FIG. 19B, TL indicates the above-described limited
time.
[0111] FIG. 19C is a graph showing the cold release time when the
cold storage is performed in the limited time TL. As in the graph
of FIG. 19C, the cold release time becomes maximum at the bonding
ratio of about 50%. As in the graphs of FIGS. 19A-19C, in order to
effectively perform the cold storage in the limited time and in
order to secure the cold release time by a small amount of the cold
storage material 50, it is preferable to set the bonding ratio X at
50% or lower.
[0112] With respect to the outside surface (X+Y portion) of the
cold storage container 47, it is preferable to set the ratio X of
the contact area to be in a range of 20% to 50%, when the cold
storage container 47 is partially bonded to the outer surface of
the refrigerant tube 45. In this case, it is possible to limit a
decrease in the heat exchange performance of the cold-storage heat
exchanger to be in a range equal to smaller than 1%, while the
ratio X of the contact area can be made small.
[0113] Furthermore, the contact ratio between the cold storage
container 47 and the refrigerant tube 45 is set so that a
sufficient heat transmission amount can be secured therebetween.
Thus, it is possible to store the thermal amount in the cold
storage material 50 in a limited time, and the cold release can be
performed for a sufficient long time by using the stored thermal
quantity. Accordingly, when the vehicle engine is stopped at the
red light of a traffic intersection, a supplemental
air-conditioning effect for a vehicle compartment can be
increased.
Fourth Embodiment
[0114] Next, a fourth embodiment of the invention will be
described. In the above-described embodiments, the plural
protrusion portions 47a1 or the plural recess portions 47a2 are
formed in the cold storage container 47, so as to have uneven
shapes shown in any one of FIGS. 6, 7, 8, 9, 13, 14, 15 and 16.
However, in the fourth embodiment, ribs composed of plural
protrusion portions 47a1 are formed into reverse-V shapes (slanting
shapes).
[0115] FIG. 20 shows the shape of ribs formed on the surface of the
cold storage container 47 according to the fourth embodiment of the
invention. The cold storage container 47 is assembled to a vehicle,
such that the lower side of the cold storage container 47 in FIG.
20 is positioned on the bottom side in the top-bottom direction of
the vehicle. The plural protrusion portions 47a1 or the plural
recess portions 47a2 are formed on the surface of the cold storage
container 47, respectively in a mountain shape having a top portion
and two slanting portions at two sides of the top portion, so that
condensed water flows downwardly from the top portion to be
separated at the left and right two sides of the top portion.
[0116] Because the protrusion portions 47a1 or the recess portions
47a2 are formed in slanting shapes, the condensed water generated
on the surface of the cold storage container 47 can be separated
into the left and right sides from the mountain-shaped top portion,
and can be promptly discharged outside along the slanting portions.
Thus, it can prevent the refrigerant tube 45 and the cold storage
container 47 from being broken due to the volume expansion of the
frozen condensed water, thereby preventing a freezing crack.
[0117] Thus, even when the condensed water remains on the surface
of the cold storage container 47 and is frozen thereon, the frozen
ice can be easily removed, thereby preventing the freezing crack.
Because condensed water can flow along the slanting portions
separated into the left and right sides, the length of the slanting
portions can be made shorter, thereby improving the discharge
performance of the condensed water.
[0118] Specifically, the protrusion portions 47a1 or the recess
portions 47a2 are formed on the surface of the cold storage
container 47 such that a protrusion height of the rib of the
slanting shape is equal to or more than 0.2 mm. Furthermore, a rib
pitch, which is a clearance between adjacent protrusion portions
47a1 or a clearance between adjacent recess portions 47a2, is set
equal to or more than 3 mm. In addition, the plural ribs are
overlapped by plural layers equal to or more than three, from the
top direction of the cold storage container 47 toward the bottom
direction of the cold storage container 47.
[0119] When the air-conditioning of the vehicle compartment is
performed by using the cold-storage container 47, condensed water
may stay in the cooling fin 46 within the cooling air passage 47
(see FIG. 17 or the like), and in the cold-storage side air passage
461a between the refrigerant tube 45 integrated with the cooling
fin 46 and the cold storage container 47. In this case, when the
frost of the condensed water is caused in a low load, the cold
storage container 47 and the refrigerant tube 45 may be broken.
[0120] In the fourth embodiment, the ribs composed of the reverse
V-shaped protrusion portions 47a1 are arranged between the
refrigerant tube 45 and the cold storage container 47, so as to
reduce the amount of condensed water staying in the space between
the refrigerant tube 45 and the cold storage container 47.
[0121] Thus, it can prevent condensed water on an upper side of the
cold storage container 47 from flowing into the reverse V-shaped
rib on a lower side of the cold storage container 47. As a result,
the amount of the condensed water staying between the refrigerant
tube 45 and the cold storage container 47 can be reduced.
Furthermore, even when the freezing of the condensed water is
caused, it can remove the generated ice to an outer side (i.e.,
paper face-back direction of FIG. 17) from the space between the
refrigerant tube 45 and the cold storage container 47.
Fifth Embodiment
[0122] Next, a fifth embodiment of the invention will be described.
FIG. 21 shows the shape of ribs on the surface of the cold storage
container 47 according to the fifth embodiment of the invention.
The cold storage container 47 is assembled to a vehicle, such that
the lower side of the cold storage container 47 in FIG. 21 is
positioned on the bottom side in the top-bottom direction of the
vehicle. In the above-described fourth embodiment, the ribs are
arranged substantially by the same pitch to be overlapped from the
top direction to the bottom direction of the cold storage container
47. However, in the fifth embodiment, as shown in FIG. 21, the ribs
are arranged by different pitches to be overlapped from the top
direction to the bottom direction of the cold storage container
47.
Sixth Embodiment
[0123] Next, a sixth embodiment of the invention will be described.
FIG. 22 is a side view showing a part of rib shapes formed on a
surface of a cold storage container 47 in an evaporator, according
to a sixth embodiment of the invention. In the above-described
fourth and fifth embodiments, the ribs are arranged to be
overlapped from the top direction to the bottom direction of the
cold storage container 47, such that the left and right slanting
shapes are continuously formed in each rib. However, in the sixth
embodiment, as shown in FIG. 22, the ribs of the slanting shapes
are arranged on the surface of the cold storage container 47 such
that left and right slanting shapes are separated by a center
groove in each rib.
Seventh Embodiment
[0124] Next, a seventh embodiment of the invention will be
described. FIG. 23 is a side view showing a part of rib shapes on a
surface of a cold storage container 47 in an evaporator, according
to a seventh embodiment of the invention. In the above-described
sixth embodiment, the ribs with the left and right separated
slanting shapes are arranged substantially by the same pitch to be
overlapped from the top direction to the bottom direction of the
cold storage container 47. However, in the seventh embodiment, as
shown in FIG. 23, the ribs having the left and right separated
slanting shapes separated at its width center are arranged by
different pitches to be overlapped from the top direction to the
bottom direction of the cold storage container 47.
[0125] In the above examples shown in FIGS. 20 to 23, the reverse
V-shaped ribs or the slanting-shaped ribs are arranged on the
surface of the cold-storage container 47 such that the plural
protrusion portions 47a1 or the plural recess portions 47a2 are
overlapped in the top-bottom direction of the cold-storage
container 47. Furthermore, in the ribs, the left and right slanting
portions, through which condensed water flows from a mountain tip
portion separately to the left and right sides, are formed to
extend to left and right two ends 47t of the cold storage container
47.
[0126] Accordingly, a large part of the generated condensed water
is discharged to outside from the two ends 47t on the outside
surface of the cold storage container 47. Therefore, it is
difficult for the condensed water to be stored in a lower portion
of the cold storage container 47, thereby preventing a freezing
break in which the refrigerant tube 45 and the cold storage
container 47 are broken in the lower portion.
[0127] Furthermore, in the plural protrusion portions 47a1 or the
plural recess portions 47a2, the left and right slanting portions,
through which condensed water flows from a mountain tip portion
separately to the left and right sides, are formed to extend to
left and right two ends 47t on the outside surface of the cold
storage container 47. In addition, as shown in FIG. 20, the plural
protrusion portions 47a1 or the plural recess portions 47a2 are
provided, such that a cross angle .theta. between a straight line
and an extending line of the slanting portions are set in a range
of 30-60 degrees. Here, the straight line is a connection line
connecting a pair of the left and right two ends 47t by the
shortest distance, as shown in FIG. 20. Thus, even when the vehicle
is tilted on a slop, a draining performance of the condensed water
can be sufficiently obtained.
[0128] Furthermore, the protrusion portions 47a1 of the cold
storage container 47 and the refrigerant tube 45 are brazed to be
in closely contact, by an area equal to or larger than 80% with
respect to the opposite surface between the plural protrusion
portions 47a1 of the cold storage container 47 and the refrigerant
tube 45. Thereby, condensed water can be certainly discharged to
the outside of the cold storage container 47 along the slanting
portions of the protrusion portions 47a1.
Eighth Embodiment
[0129] Next, an eighth embodiment of the invention will be
described. In the above-described embodiments, the refrigerant
passage portion of the evaporator 40 is configured by the headers
41, 42, 43, 44 and the refrigerant tubes 45 located between the
headers 41, 42, 43, 44, as shown in FIGS. 2 and 3.
[0130] The respective refrigerant tubes 45 are made to communicate
with corresponding headers 41, 42, 43, 44 at the ends of the
refrigerant tubes 45. Moreover, each refrigerant tube 45 is a flat
tube having multi-holes, which is formed by the extrusion process
to have therein plural refrigerant passages extending in the tube
longitudinal direction. The ribs on an uneven surface can be formed
via the extrusion process by using a pressurization roller,
similarly to the method described in JP 2004-3787A.
[0131] In the eighth embodiment, plural pairs of plates, each pair
having integrated tank portion and refrigerant tube portion, are
stacked in a stacking direction, thereby forming a heat exchanger.
A stack-type heat exchanger described in JP 2001-221535 can be used
and incorporated by reference in the present embodiment.
[0132] The ribs with the uneven shape, composed of the protrusion
portions 47a1 and the recess portions 47a2, can be formed on a
surface of a cup-shaped tube (drawn-cup tube) formed by overlapping
a pair of plates, by using a method described in JP 2004-3787A that
is incorporated by reference in the present embodiment. The
contents described in JP 2004-3787A and JP 2001-221535A can be
incorporated herein by reference, as the technical contents of the
present specification.
[0133] FIG. 24 is a front view of an evaporator with a cold storage
material in the eighth embodiment formed, by the above-mentioned
stacking plates. FIG. 25 is a left side view showing the evaporator
with the cold storage material of FIG. 24. As shown in FIG. 24 and
FIG. 25, the tank portion and refrigerant tube portion of the
evaporator are formed integrally by overlapping a pair of plates.
Plural pairs of the overlapped plates are stacked, and the cold
storage containers 47 are inserted partially between the stacked
parts. In FIGS. 24 and 25, uneven shapes on the surface of the
cold-storage container 47 or the refrigerant tube 45 are not shown.
Moreover, in FIG. 24 and FIG. 25, parts corresponding those of FIG.
2 are indicated by the same reference numbers.
[0134] FIGS. 26A and 26B are schematic sectional views by
comparison, showing an evaporator in which a refrigerant tube is
manufactured by a drawn-cup tube according to the eighth
embodiment, and an evaporator in which a refrigerant tube is
manufactured by extrusion. That is, a refrigerant tube 45 of the
eighth embodiment shown in FIG. 26A is a drawn-cup tube.
[0135] In FIG. 26A, an air-side fin 46 is provided in a cooling air
passage 460 on the left side, a refrigerant tube 45 of a drawn-cup
type having therein an inner fin 45f is provided at one side of the
air-side fin 46, and a cold storage container 47 having an uneven
surface is bonded to a surface of the refrigerant tube 45 opposite
to the surface on the air side.
[0136] The air-side fin 46, the refrigerant tube 45 and the cold
storage container 47 are configured as one unit. For example,
Plural units can be overlapped to configure an evaporator. Another
air-side fin 46 may be bonded to the right surface of the cold
storage container 47 shown in FIG. 26A to form a unit.
Alternatively, another refrigerant tube 45 having therein an inner
fin 45f may be bonded to the right surface of the cold storage
container 47 to form a unit.
[0137] The refrigerant tube 45 of FIG. 26B is formed by extrusion
similarly to the first embodiment. FIG. 26B is a modification of
the first embodiment. In FIG. 26B, an inner fin 47f is not provided
in the cold storage container 47, which is different from the first
embodiment shown in FIG. 4. In FIGS. 26A and 26B, the evaporator
formed by using a drawn-cup method with laminated plates, is
compared with the evaporator formed by extrusion.
Ninth Embodiment
[0138] Next, a ninth embodiment of the invention will be described.
FIGS. 27A and 27B are schematic sectional views by comparison,
showing an evaporator in which a refrigerant tube is manufactured
by a drawn-cup tube, and an evaporator in which a refrigerant tube
is manufactured by extrusion, according to the ninth
embodiment;
[0139] That is, a refrigerant tube 45 of the ninth embodiment shown
in FIG. 27A is a drawn-cup tube. In FIG. 27A, an air-side fin 46 is
provided in a cooling air passage 460 on the left side, and a
refrigerant tube 45 of a drawn-cup type having therein a
refrigerant tube fin 45f (inner fin) is provided at one side of the
air-side fin 46.
[0140] One surface of the refrigerant tube 45 is formed in uneven
to have protrusion portions 45a1 as ribs, and recess portions 45a2.
A flat cold storage container 47 without an uneven portion on the
surface is bonded to a surface of the refrigerant tube 45 opposite
to the surface of the air-side fin 46. Thus, a cold-storage side
air passage 461a is formed between the recess portions 45a2 of the
refrigerant tube 45 and the flat surface of the cold storage
container 47.
[0141] The air-side fin 46, the refrigerant tube 45 and the cold
storage container 47 are configured as one unit. For example,
Plural units can be overlapped to configure an evaporator. Another
air-side fin 46 may be bonded to the right surface of the cold
storage container 47 shown in FIG. 27A to form a unit.
Alternatively, another refrigerant tube 45 having therein an inner
fin 45f may be bonded to the right surface of the cold storage
container 47 to form a unit.
[0142] The refrigerant tube 45 of FIG. 27B is formed by extrusion
similarly to the first embodiment of FIG. 4. FIG. 27B is a
modification of the first embodiment. In FIG. 27B, the surface of
the cold storage container 47 is formed to be flat without an
uneven portion, the protrusion portions 45a1 and the recess
portions 45a2 are formed on the one surface of the refrigerant tube
45 to form ribs, and an inner fin 47f is not provided in the cold
storage container 47, which are different from the above-described
first embodiment. In FIGS. 27A and 27B, the evaporator formed by
using a drawn-cup method with laminated plates, is compared with
the evaporator formed by extrusion.
Tenth Embodiment
[0143] Next, a tenth embodiment of the invention will be described.
FIG. 28 is a schematic sectional view showing a part of an
evaporator similar to FIG. 4 of the first embodiment, according to
the tenth embodiment of the invention. FIG. 29 is an enlarged
schematic sectional view showing a part Z33 of FIG. 28;
[0144] FIG. 30 is an enlarged schematic sectional view showing a
part Z34 of FIG. 28; FIG. 31 is a graph showing a variation state
of an evaporator temperature in accordance with an interruption
operation of a clutch connected to a compressor according to the
tenth embodiment. FIG. 32 is a side view showing reversed V-shaped
ribs formed on a surface of a cold storage container 47 of the
evaporator of FIG. 28.
[0145] As shown in FIG. 28, the refrigerant tubes 45 are multi-hole
tubes, each of which has therein a plurality of refrigerant
passages extending in a tube longitudinal direction. Left and right
refrigerant tubes 45a and 45b (45) are arranged at two sides of a
cold storage container 47 having therein an inner fin 47f, and two
cooling air passages 460 for performing heat exchange with air are
provided respectively at left and right sides of the left and right
refrigerant tubes 45a and 45b.
[0146] The refrigerant tube 45 and the cold storage container 47
contact at positions, and are bonded at the contact positions by a
brazing material 33r, as shown in FIG. 29. When a void 33v exists
in the brazing material 33v1, the condensed water 33v1 may stay in
the void 33v of the brazing material 33v1.
[0147] In the cold-storage side air passage 461a formed by the
recess portions 47a2 on the surface of the cold storage container
47 of FIG. 28, a space 34v is provided as shown in FIG. 30. When
air to be conditioned is blown by a cooling fan (not shown), air
flows in the space 34v, and water contained in air is condensed as
a condensed water 34v1. In this case, the condensed water 34v1
easily stays in the space 34v. The space 34v is adapted as the
cold-storage side air passage 461a, when the cold storage material
releases cold in the cold storage container 47.
[0148] As shown in FIG. 31, the temperature of the evaporator (cold
storage heat exchanger) changes to be repeated in accordance with
interruption of a clutch connected to the compressor 10 of FIG. 1,
thereby repeating freezing and solution of condensed water as shown
in FIG. 31. In order to prevent a freezing break, a width W of a
bonding flat portion of FIG. 29 is set equal to or smaller than 0.8
mm.
[0149] Furthermore, the ribs formed by the protrusion portions 47a1
adjacent to the recess portions 47a2 are formed in reverse V-shape,
as shown in FIG. 32 when being viewed from the arrow Z36 of FIG.
30. Therefore, the condensed water 34v1, staying in the space 34v
of FIG. 30 formed by the recess portion 47a2 on the surface of the
cold storage container 47, can be discharged outside of the cold
storage container 47, as in arrows Y36 of FIG. 32.
[0150] The width dimension of the recess portion 47a2 between the
protrusion portions 47a1 is set, such that condensed water can be
drawn in the direction shown by the arrow Y361 from bottom by using
the clearances between the protrusion portions 47a1. Thus, even
when condensed water becomes ice, the ice can easily fall on the
surface of the cold storage container 47, and can be easily removed
to the outside. Therefore, it can prevent a stress for causing a
freezing break from being generated.
[0151] In the cold storage heat exchanger in which the cold storage
container 47 is integrated with the cooling fins 46a, 46b of the
cooling air passage 460 for air-conditioning of the vehicle
compartment, if condensed water stays in the cold-storage side air
passage 461a between the refrigerant tube 45 and the cold storage
container 47 so that a freezing (frost) of the condensed water is
generated in a low load, the cold storage container 47 and the
refrigerant tube 45 may be broken. According to the tenth
embodiment, the reverse V-shaped ribs are arranged in the spaces
between the refrigerant tube 45 and the cold storage container 47
as shown in FIG. 32, so as to reduce an amount of condensed water
staying in the spaces between the refrigerant tube 45 and the cold
storage container 47.
[0152] Thus, in the tenth embodiment, it can restrict condensed
water on the cold storage container 47 from flowing, from an upper
side rib to a lower side rib on the surface of the cold storage
container 47. As a result, the amount of the condensed water
staying between the refrigerant tube 45 and the cold storage
container 47 can be reduced in the cold storage heat exchanger.
Furthermore, even when the freezing of the condensed water is
caused, it can easily remove the generated ice to an outer side
from the space between the refrigerant tube 45 and the cold storage
container 47.
* * * * *